Introduction to
Geographic Information Systems in Forest Resources |
What
is ArcView GIS?
ArcView GIS software is a desktop GIS with an easy-to-use, point-and-click
graphical user interface that lets you easily load spatial and tabular data
so you can display the data as maps, tables, and charts. ArcView provides
the tools you need to query and analyze the data and present your results
as presentation-quality maps.
-ESRI, Introduction to ArcView GIS
ArcView has a number of features that make it a good tool for learning and
using GIS. Other GIS software may have similar features.
- GUI.
Unlike most GIS software of the past, ArcView provides a graphical user interface.
This provides a number of benefits:
- No need to remember thousands of commands and command arguments.
- Fast and accurate typing skills are not an issue.
- Most commands and operations are available by navigating the ArcView
menu and dialog structure.
But do not be fooled by ArcView's apparent simplicity. Many operations are
hidden below several layers of pulldown menus and dialog boxes. It will take
skill and memory in order to get good at making the most out of ArcView.
- Desktop Use.
Only recently have computers become cheap and powerful enough to supply the
resources needed for a fully-functional GIS on a typical office or school
desktop. At the same time, much effort has been undertaken by software manufacturers
to increase the functionality and ease of use of their products. In the recent
past, GIS software was able to be used only on high-end UNIX or VMS workstations.
Today, PCs are powerful enough to handle GIS applications, and the software
is easy enough to get started using, that you will become productive within
the first few hours of using ArcView.
- Database Access.
ArcView uses SQL (structured query language) connections to external databases
(such as Oracle, Informix, or Access). Many large databases have been built
on these applications. If you know how to use SQL syntax, you can connect
to an external database, issue an SQL statement, and return results that can
be viewed in a spatial context.
- Customization & Programming.
ArcView ships with a robust programming language (Avenue). Avenue scripts
can be used to automate complex or repetitive tasks, or to create entire applications.
- Extensions to Increase Functionality.
Several extensions are shipped with ArcView, and others are available for
free or at additional cost. These extensions increase the functionality of
ArcView, either by adding features commonly found in other GIS software (such
as the Xtools extension we will use in the
module on vector analysis, as well as the Spatial Analyst, Network Analyst,
and 3-D Analyst). Some of the built-in optional extensions are used for direct
use of CAD data, digitizer support, projections, and hydrologic modeling.
It is also possible to create your own extensions to run custom tasks or applications.
As we go through the quarter, you will understand what all this means.
A frequently asked question in this course is "Why are we using ArcView
3.2 instead of ArcInfo or ArcGIS?" Here are my answers:
- This course is about learning to use GIS as a tool in natural resource applications.
The course is not a training course in GIS software (although
many of you will attain proficiency with software over the quarter). For this
reason, it does not really matter what software we use, as long as that software
will allow you to learn about GIS.
- ArcGIS, at the time of this writing (
) is not what I would consider ready for use in a classroom setting:
- Not all of the functionality of even ArcView 3.2 has been implemented
in ArcGIS.
- ArcGIS is a lot more complicated to use (more parts in different places,
even more multi-leveled GUI). You will learn more about how to use a GIS
in one quarter with ArcView than with ArcGIS.
- ArcGIS requires a powerful computer. Most of the labs used for teaching
and study will not have computers powerful enough to run ArcGIS without
a lot of wait time and a lot of down time due to software crashes
- ArcView 3.2 still has the largest user base of any GIS software in use today.
- It will take me a long time to update all of these detailed class notes.
Syllabus